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Equity Compensation, Employment Agreements and Other Benefit Plans (Narrative) (Details) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Sep. 30, 2018 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019
Share based compensation |  |  |  |  |  |
Maximum shares authorized for grant | 18,000,000.0 |  |  | 18,000,000.0 |  |
Shares available for grant (in shares) | 14,800,000 |  |  | 14,800,000 |  |
RSUs |  |  |  |  |  |
Share based compensation |  |  |  |  |  |
Awards granted (in shares) |  | 160,025 | 0 | 1,204,713 | 912,525 |
Forfeitures (in shares) |  |  |  | 0 | 20,000 |
Unrecognized compensation cost | $ 9,700,000 |  |  | $ 9,700,000 |  | $ 5,500,000
Period for recognizing unrecognized compensation cost |  |  |  | 2 years 1 month 6 days |  |
Restricted shares of common stock |  |  |  |  |  |
Share based compensation |  |  |  |  |  |
Awards granted (in shares) | 79,545 |  |  | 79,545 | 0 |
Share-based awards outstanding (in shares) | 0 |  |  | 0 |  |
Dividend Equivalent Rights |  |  |  |  |  |
Share based compensation |  |  |  |  |  |
Equivalent rights payment |  | $ 256,000 |  | $ 276,000 | $ 497,000 |
Equity Compensation Plan |  |  |  |  |  |
Share based compensation |  |  |  |  |  |
Maximum number of common shares that can be granted to participant in any one year |  |  |  | 2,000,000.0 |  |
Period during which a participant can be awarded the maximum number of shares allowable under the Plan |  |  |  | 1 year |  |
Maximum percentage of common shares that can be owned or deemed to be owned by a participant (more than) |  |  |  | 9.80% |  |

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- Definition Aggregate payments on account of dividend equivalent rights during the period. Dividend equivalent rights relate to participating securities representing share-based payment awards that contain nonforfeitable rights to dividends. + References No definition available. + Details
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- Definition The highest quantity of shares a participant can be awarded in any one year under the plan. + References No definition available. + Details
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- Definition Represents the period during which an employee can be awarded the maximum number of shares allowable under the Plan. + References No definition available. + Details
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- Definition The maximum percentage of common shares that can be owned or deemed to be owned by a participant. If the maximum ownership or deemed ownership is attained no awards may be granted to that participant. + References No definition available. + Details
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- Definition Amount of cost not yet recognized for nonvested award under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Number of shares authorized for issuance under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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